The commission's report proposes dramatic reforms to help thwart another attack. But do they make sense, and will they ever be implemented?

The logo of the U.S. Central Intelligence Agency is swept clean in the lobby of the CIA headquarters in Langley, Virginia.

On Sept. 11, declared the commission investigating the 9/11 attacks in its 567-page report, the "United States became a nation transformed." From the shipyards of Seattle to the conventioneer-stuffed ballrooms of Boston, the scramble to prepare for the possibility of another attack offered a panorama last week of the country's metamorphosis. Police divers in the Port of Seattle combed the hulls of cruise ships for explosive devices. The Secret Service ordered that all food deliveries to Boston's Fleet Center, site of the Democratic National Convention, be tested for radioactive material. In Hennepin County, Minn., 2,500 government employees did a simulated evacuation...